Semiconductor quantum dot nanoparticles are potent fluorphores for in vitro and in vivo imaging. Their tunable, size-dependent and strong emission characteristics make them outperform standard organic dyes in many applications. However, a drawback to developing applications with semiconductor quantum dots in biomedicine is the toxic nature of their constituent elements, as they typically consist of toxic binary compounds such as cadmium selenide. Means to alleviate and or passivate this toxicity are needed before quantum dots can gain widespread application, particularly for in vivo applications. This project will create a universal platform for protecting quantum dots using a new type of coating that will help solve several long-standing problems with quantum dots. The new coating is impermeable under physiological conditions, will allow stabilization of doped semiconductor quantum dots and can be conjugated to biomolecules and other targeting agents. This research will create new coatings for fluorescent quantum dots, which are a new type of nanoparticle that can be used to image disease with light emission and for use in other in medical diagnostic procedures. Public health benefits resulting from this project will include safer, more potent means for diagnosis and treatment of disease, both in laboratory tests and for patients. [unreadable] [unreadable] [unreadable]